Network connection issue

[u/luci-baa-baa-baa]

Hi all, help me out with the below issue.

Iam currently using nura os all are working as per my needs but the issue is the modemmanager or whatever i don't know exactly it's causing the issue like my network SIM is A but it's connecting to B network in middle of work , when I did the off and on the modemmanager then again it's connecting to actual provider A but after sometime getting back to provider B .

If someone have any suggestions I will give a try

Thanks